This invention relates to seed testing.
It is known to test seeds to assess seed quality or viability or to predict performance of the seeds in the field. Generally, these tests are performed in accordance with the Association of Official Seed Analysts Rules (AOSA) or the International Rules for Seed Testing to provide repeatability for comparing different seed lots. The tests emphasize reliability, standardization, efficiency and cost.
For example, one known standardized test is referred to as an accelerated aging test. This test is used to predict the effects of storage on seeds as indicated by the percentage of healthy seedlings derived from seeds subjected to accelerated aging. Kits are commercially available for this test. In one accepted version of this test, seeds are suspended above water at a warm temperature for a period of time. The temperature and time may vary within species between hybrid or inbred lines and may vary from species to species. They are in accordance with accepted standards such as the International Rules for Seed Testing or the AOSA. After accelerated aging, the seeds are typically tested for viability by standard warm germination protocols.
Accelerated aging of seeds is conducted within an assembly comprised of a container, a lid for the container and a removable seed-holding tray that fits within the container. The tray includes a horizontal screen support for holding the seeds above water in the container. In use, prior to starting the test, several accelerated aging units are prepared. In preparing the units, water is dispensed into the container, the trays are placed in the containers and seeds are placed on the screens. The containers are marked and the test is started. The test is started by placing the closed containers, containing water, a seed-holding tray in which a screen is incorporated to suspend seeds above the water in the container, and seeds residing on top of the screen of the seed holding tray in an environment where the container or containers will have the desired incubation temperature.
In a prior art type of accelerated aging assembly, the tray includes posts, a screen support and the screen. The posts hold the screen and screen support at a height above the expected water level. The screen support includes vertical walls with a horizontal bottom ledge that receives the screen. It has been discovered that the prior art method and apparatus for performing accelerated aging tests can advantageously be improved in several ways, such as: (1) by reducing the cost of manufacture; (2) reducing the time required for performing the tests; (3) reducing the number of steps needed to perform the test and thus reducing the opportunities for error; and (4) reducing microbial cross contamination problems that existed in the prior art non-disposable test kits. The cross contamination problems with the prior art non-disposable test kits are an undesirably high likelihood of cross contamination between tests and the consequent effort needed in sterilizing the test-kit components between successive uses of the test kits for the prior art non-disposable test kits.
Another type of standardized test is known as a saturated cold germination test. This test is used to measure the ability of seeds to germinate in cold, high moisture and anaerobic soil environments and to assess the general vigor of seed lots. It is intended to simulate early season adverse field conditions. Standardized saturated cold test procedures are normally used. In one known version of this test, corn seeds are inserted with the embryo down on saturated soil and maintained at a low temperature for several days or for a prescribed period of time and then moved to a warm germination temperature. The test procedures for other species differ from corn and the temperature and time values for other species are provided by the International Rules for Seed Testing or the Association of Official Seed Analysts Rules. A typical saturated cold test assembly consists of water saturated paper, such as water saturated towels overlaid with loose soil. The seeds are inserted in the loose soil. The saturated cold test assembly is then maintained at a low temperature for a prescribed time period before being moved to a warm temperature to complete the test.
The prior art methods and apparatuses can benefit from improvements to reduce labor and time in the tests and to increase standardization and repeatability.